The pressure-sensitive adhesive tape according to the present invention has an excellent balance between the adhesive strength and the cohesive strength and thus can be advantageously applied to various adherends. In one aspect thereof, the pressure-sensitive adhesive of the present invention, when it is applied to a wall paper, can be released from the wallpaper without damaging the wallpaper. Further, in another aspect thereof, the pressure-sensitive adhesive of the present invention, when it is applied to a wide variety types of adherents having significant surface irregularities or a roughened surface such as a wall paper, film or sheet having a significant irregularity in the surface or walls such as mortar wall, lithin-finished wall or concrete wall, can be strongly adhered to such adherends, and can be released from the adherends without damaging the same.
According to the present invention, the above-described aspects can be attained by a pressure-sensitive adhesive composition which comprises a cohesive component comprising a styrene-based block copolymer, and a basic component.
Also, according to the present invention, a pressure-sensitive adhesive tape comprising a stretchable substrate and a pressure-sensitive adhesive layer provided on at least one surface of the substrate, the pressure-sensitive adhesive layer comprising the above-described pressure-sensitive adhesive composition comprising a cohesive component and a basic component of the present invention, is provided.
Furthermore, according to the present invention, an adhesion structure comprising the pressure-sensitive adhesive tape of the present invention and an adherend having attached thereto the pressure-sensitive adhesive tape through the pressure-sensitive adhesive layer, wherein the pressure-sensitive adhesive tape can be separated from the adherend by stretching the substrate of the pressure-sensitive adhesive tape, is provided.
As well understood from the following detailed description, when the pressure-sensitive adhesive composition of the present invention is used, a removable pressure-sensitive adhesive tape capable of so-called “stretch-release”, which can be, after attaching to an adherend, easily removed from the adherend by stretching the pressure-sensitive adhesive tape, can be provided. The pressure-sensitive adhesive tape of the present invention not only requires no pulling with excess force on separating and removing it from an adherend but also causes no adhesive transfer on the adherend or no damage of the adherend itself.
The pressure-sensitive adhesive tape of the present invention is excellent in the balance between the adhesive force and the cohesive force and can be advantageously applied to various adherends. For example, when applied to a vinyl chloride-based adherend containing a plasticizer, the pressure-sensitive adhesive tape of the present invention can be prevented from reduction in the adhesive property due to migration of the plasticizer into the pressure-sensitive adhesive composition layer.
Further, the application of the pressure-sensitive adhesive tape of the present invention is not restricted to the vinyl chloride-based adherends, and the adhesive tape can be strongly applied to a wide variety types of adherents having significant surface irregularities or a roughened surface such as a wall paper, film or sheet having a significant irregularity in the surface or walls such as mortar wall, lithin-finished wall or concrete wall. When it is applied to such adherends, the adhesive tape can be released from the adherends without damaging the same. For example, the film-type adherends suitable in the practice of the present invention include, but not restrictive to, a film of ethylene-vinyl alcohol copolymer resin and a film of styrene-(meth)acrylate copolymer resin. Of course, the adherends referred to herein include a vinyl chloride-based adherend particularly containing a plasticizer.
Furthermore, even when used under high-temperature and high-humidity conditions (in a wet and hot environment) or in an environment using water, the pressure-sensitive adhesive tape of the present invention can be free from reduction in the adhesive strength or other properties and can be stably used over a long period of time.
The adhesion structure of the present invention comprises the pressure-sensitive adhesive tape of the present invention in combination with an adherend and therefore, this adhesion structure can express the above-described noticeable effects ascribable to use of the pressure-sensitive adhesive tape and can be advantageously used in various fields.
As described above, the present invention provides
(1) a pressure-sensitive adhesive composition comprising a cohesive component containing a styrene-based block copolymer, and a basic component,
(2) a pressure-sensitive adhesive tape, particularly a removable pressure-sensitive adhesive tape capable of being “stretch-released”, comprising a stretchable substrate and a pressure-sensitive adhesive layer provided on at least one surface of the substrate, the pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition of the present invention, and
(3) an adhesion structure equipped with such a pressure-sensitive adhesive tape.
The pressure-sensitive adhesive composition, pressure-sensitive adhesive tape and adhesion structure of the present invention each is described by referring to the attached drawings.